Blue/green powder on outside of copper pipe.

[Daryll]

Hi all....

I'm wondering if some of my copper pipes are getting corroded where they enter a concrete floor, and should I be thinking about re-routing the pipework?

We have an extension which, i think, used to be the old outside toilet/coal shed, (1950's ex council house). This extension has been turned into a utility room and cloakroom with hot and cold water pipes coming through the wall from the kitchen, down into the concrete floor, re-appearing about 4 ft away to supply the washing machine and cloakroom.
These pipes were there when we moved in, about 15 years ago.

Where the pipes enter and leave the floor, there is a lot of blue/green powder on the pipes. Is this the pipes corroding, and is there a risk of them starting to leak??

I'm tempted to re-route the pipework above ground (up the wall, over a door and then down to re-join the washing machine/cloakroom supply), does this sound a good idea?

TIA

Daryll.

Untitled

• Daryll
• 28 Nov 2011
• 1

Untitled

• Daryll
• 28 Nov 2011
• 1

 

[HERTS P&D]

If the pipes that go into the floor are not protected then they should be re-routed as the concrete will 'eat' into the pipework and will cause a leak.

Andy

 

[Daryll]

Thanks Herts,

I've no idea whether the pipes are protected in the concrete, but I can't see the end of anytape or protective sleeving, so I'm guessing not.

Ok, something else to add to my "to do" list....

 

[Agile]

You might as well wait until a leak starts.

Many pipes like that go for 10 years!

Tony

 

[tim00]

Most useful advice already given, but for what it's worth:
There is a flap of a plastic sheet/membrane showing in the second pic. if the plastic is isolating the copper from the aggressive concrete then it could be some mix of degrading chemicals in the ground that is giving such a heavy, local patina.
Excessive or uncleaned flux will also cause erosion of the pipework. But, as has been said, best maybe clean up with wire wool and leave well alone.

If, at some future date, you wish to, or have to, run new pipework, then abandon the groundwork and run the tube above ground.

Are the pipes painted or coated with something above the corrosion?

 

[Agile]

Its most unlikely there is any further acid around after so long.

I would say leave alone. Using wire wool will reduce the copper thickness which is the last thing you want to do.

If there was still any acid from flux still present then washing with warm mild sodium carbonate solution ( or bi-carbonate ) would neutralise it.

Tony

 

[Daryll]

Thanks Gents,

It sounds like its not a major problem, so i'll only re-route the pipework if/when a leak does develop.

We're planning on giving this extension a facelift in the next few months, so I'll just give the pipes a gentle clean to get rid of the powder and give them another coat of paint

Regards,

Daryll.